1. Field of the Invention
The present invention relates to an image forming apparatus of an electro photographic system, such as a printer, a copying machine, and the like.
2. Description of the Related Art
In forming an image by the electro photographic system, a charging amount of toner is reflected to an image quality such as image density, and the like. For this reason, humidity dominating the charging amount is also a parameter to be obtained. Accordingly, Japanese Patent Laid-Open No. 2005-195886 discloses a technology of including a humidity detection unit in a toner bottle containing a replenishment toner to detect a humidity of toner.
Japanese Patent Laid-Open No. 2005-195886 discloses detecting a humidity of an outer wall of a toner cartridge as a humidity of toner since the humidity of the toner within the toner cartridge is familiar with humidity around the toner cartridge.
However, upon figuring out the humidity of the toner with more precision, the method is difficult to figure out a sufficient humidity.